The present invention relates to a dynamic mixer, comprising a rotor housing in which a mixing rotor is arranged and which is closed on the inlet side by a cover on which inlets for the components are arranged.
Particularly when mixing components in different volumetric amounts as they are e.g. used for producing dental impression materials the difficulty arises that the two components should be mixed at the correct mixing ratio at the beginning of the mixing process already. If no particular measures are taken, the component whose volumetric content is smaller, e.g. a catalyst, is absent or not present in a sufficient amount at the beginning of the paste strand discharged from the mixer. The result is an unsatisfactory mixing quality such that e.g. the hardening capability of the casting compound is not ensured. Another weakness of the currently available mixers is the inclusion of air bubbles, which affects the impression quality.
EP-A2-1 402 940 discloses a dynamic mixer having a detour channel in order to retard the entrance of the component having the larger volumetric amount into the mixing chamber. This measure has the disadvantage that a high pressure is required for delivering that component to the mixing chamber through the detour channel, particularly if it is highly viscous.